A clutch of the above kind is described in the specification of French published patent application No. FR 2 623 862A. In that specification, the intermediate discs are coupled with the reaction plate for rotation with the latter, the intermediate discs being movable axially by virtue of a plurality of intermediate driving members in the form of spacing blocks. The intermediate discs define mortices.
In this way, a coupling, of the tenon and mortice type, is formed. The intermediate discs carry a first part of this coupling, while the intermediate driving members carry the second, complementary, part of the coupling. The first part of the coupling includes at least two elements, which are mortices in the arrangement described in the above mentioned French patent specification.
In addition, in connection with clutches of the kind intended particularly for fast motor vehicles such as racing or sports cars, it is desirable or essential for the clutch to be able to be conveniently inspected and subsequently refitted. Accordingly, a specific problem arises in that the two faces of the intermediate discs, which in certain cases are not adapted to be reversed, i.e. each disc must be fitted the right way round. This may for example be due to the nature of the materials used, or the nature of the connection between the surfaces after wear between the intermediate disc and its associated friction disc has taken place.